I just purchase a center channel to pair with my ceiling Polks rc80i. I bought my Denon 1913 about 1 month ago and set up the system to 5.1......I bought my center yesterday Polk Tl1 and went thru the audessey set up and i hear sound from the center channel when I go thru the set up but when play tv thru hdmi i don't hear any sound coming from the center? i 've switched out the center to one of my old centers and still no sound......what gives? is my denon not working?

What kind of programming are you watching, and what mode do you have it in, when you press the Movie button? If all you have is three speakers, depending on what you are watching on tv, depends on if you get three channel, or only two channel (stereo no center).